Gang mower

ABSTRACT

A gang mower for garden tractors includes a frame, a hitch and either three, five or seven reel-type mower units attached to the frame. The frame is attached to each of the mower units higher than the rear roller axis of the mower unit, lower than the forward wheel axis of the mower unit and a sufficient distance away from the forward axis that a majority of the frame&#39;s weight is supported by the rollers rather than the forward wheels of the reel-type mowers. In action, the frame pushes the reel-type mowers forward when the frame is pulled forward by a garden tractor. The attachment and distribution of weight assures that the rear rollers of each of the individual mower units is always in contact with the ground. At the same time, the forward drive wheels are leveraged downward in order to insure sufficient friction to turn the mower blades without the inclusion of unnecessary and undesirable weight. In one aspect of the invention the outer mower units and hitch can be pivoted to an upright stowed position to facilitate storage of the gang mower in a relatively small space. This pivoting aspect of the frame along with the pivoting attachment of the individual mower units to the frame allows the gang mower to hug the contour of the ground.

FIELD OF THE INVENTION

The present inventions relates generally to reel-type gang mowers, andin particular to gang mowers for use with home garden tractors or draftanimals.

BACKGROUND OF THE INVENTION

Reel-type gang mowers have long been known in the art, and are mostoften identified with golf courses and other wide open areas requiringan attractive contoured cut. Gang mowers are often recognized for theirability to mow a given area in a significantly shorter amount of timethan that possible with conventional power mowers. This is due in partto the relatively large swath (8 feet or more) possible with gangmowers, whereas power mowers typically cut a swath of four feet or lesswith each pass. Gang mowers can also usually be pulled faster than acomparable power mower without sacrificing on the quality of the cut.Therefore, not only are gang mowers well known for there ability to makean attractive contoured cut, they are also known to be significantlyfaster than the largest counterpart power mowers, provided one has atractor with sufficient power to pull the gang mower.

Most prior art gang mowers are relatively heavy and normally require arelatively powerful tractor to pull the gang mower. In other words, homegarden tractors have typically not been sufficiently powerful to pullmost commercially available gang mowers. Thus, most if not allhomeowners with relatively large estates (several acres or more) mustchoose between one of a variety of home garden tractors with power mowerattachments for use in mowing their large lawns. These tractor powermowers typically have a rotating blade on the order of three feet indiameter but rarely, if ever, exceeding four feet in diameter. This isbecause larger decks, 40 inches or larger, will often scalp the groundon one side while being too far off the ground on the other when themower encounters even moderate contouring. Thus, the homeowner thatdesires an attractive cut must necessarily choose a smaller sized deckand spend multiple hours each week riding his or her lawn mower back andforth around their yard. Reel-type gang mowers have not been a realisticalternative to these homeowners because the gang mowers of the prior arttypically require a large storage area, and relatively larger tractors,which are prohibitively expensive and also require their own addedstorage space.

One of the reasons that gang mowers of the prior art are relativelyheavy is because the individual mower units are typically attached tothe gang mower frame in a way that requires a relatively large downwardforce in order to maintain the individual mower units in proper contactwith the ground at all times. In particular, prior art gang mower framesare typically attached above and forward from the individual mowerunits, with the consequence being that the frames (and mower units) mustbe relatively heavy in order to maintain both the drive wheels and thetrailing rollers of the individual mower units in contact with theground. Examples of such gang mowers include but are not limited to thegang mowers shown in Braun U.S. Pat. No. 1,663,900, Worthington U.S.Pat. No. 1,902,928 and Blue et al. U.S. Pat. No. 2,830,421.

A more recent gang mower assembly illustrated in Tobin Jr. U.S. Pat. No.4,287,706, overcomes some of the weight problems of the prior art toproduce a gang mower suitable for use with home garden tractors. TobinJr. accomplishes this by making a gang mower frame that attaches to thehandle studs of the individual reel-type mower units. Thus, in theorythe frame pushes forward and downward on the handle studs of theindividual mower units when the frame is pulled forward by a gardentractor. In other words, the individual mowers units are pushed forwardwhen the frame is pulled. While this concept apparently permitted alower weight frame suitable for use with garden tractors, a number ofproblems have persisted in the Tobin Jr. gang mower design. Not theleast of which is the recognition by Tobin that a spring is oftenrequired in order to apply a moment about the handle studs of the mowerunits in order to help maintain the rollers of the individual mowers onthe ground at all times. It is well known that it is absolutely criticalfor the proper functioning of a reel-type mower that both the drivewheels and the trailing roller always remain in contact with the ground.Tobin Jr., also suffers from a number of other problems that havepersisted in the art, including the inability to back up when the gangmower is attached to a tractor, the inability to store the gang mower ina relatively small space, the inability of the gang mower to properlyfollow lawn contours, and other problems.

In view of the prior art, what is needed is a reel-type gang mower thatis low weight, capable of being stored in a relatively small space, issuitable for use with home garden tractors and overcomes many of thepracticality problems encountered with the various gang mowers of theprior art.

SUMMARY OF THE INVENTION

In responding to this need, the present invention provides a gang mowerfor garden tractors comprising a frame, a hitch attached to andextending forward from the frame, and a plurality of reel-type mowersattached to the frame. Each of the reel-type mowers has a pair offorward wheels and a rear roller. The forward wheels are rotatable abouta forward axis, and the rear roller is rotatable about a rear axis thatis substantially parallel to the forward axis. The frame is attached toeach of the reel-type mowers at a position higher than the rear axis,lower than the forward axis and a sufficient distance away from forwardaxis that a majority of the frame's weight is supported by the rollersof the reel-type mowers instead of by the forward wheels of thereel-type mower units. When in action, the frame pushes the reel-typemower forward when the frame itself is pulled forward by the hitch.

The present invention can include a number of enhancements including thepossibility of a frame that is substantially rigid with respect to avertical axis such that the relative positioning of the reel-type mowersin a plane perpendicular to the vertical axis remain substantiallyconstant regardless whether the gang mower is being pulled forwardaround curves or pushed backward. Also, the reel-type mowers can beattached to the frame at pivot points that permit the individual mowerunits to pivot with respect to the frame about horizontal axes throughthe pivot points. In another enhancement the frame can include aplurality of outer portions that are attached to the central frame atpivot points that permit the outer mower units to pivot about horizontalaxes. Both pivoting enhancements allow the mower to follow lawn contoursand produce a more attractive cut. Furthermore, the outer frame unitsand the hitch can be made to pivot to a stowed position so that the gangmower can be stored in a relatively small space. Other aspects andpotential enhancements of the invention will be more thoroughlyidentified and discussed in the detailed description of the invention.

One object of the present invention is to provide a gang mower that willpermit a homeowner to mow their lawn in a fraction of the amount of timepossible with counterpart power mowers.

Another object of the present invention is to provide a gang mower forgarden tractors that overcomes the storage and backing up problems ofthe prior art.

Still another object of the present invention is to provide a relativelylight-weight gang mower.

Still another object of the present invention is to provide homeownerswith a professional looking contoured cut to their lawns at a fractionof the price possible with counterpart riding power mowers.

Another object of the present invention is to provide an improved gangmower for garden tractors.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of a gang mower for garden tractors according tothe present invention.

FIG. 2 is a side elevational view of a gang mower for garden tractorsaccording to the present invention.

FIG. 3 is a front elevational view of a gang mower for garden tractorsaccording to the present invention in its stowed configuration.

FIG. 4 is an enlarged side elevational view of a portion of a gang mowerframe according to one aspect of the present invention.

FIG. 5 is a side diagrammatic illustration of a reel-type mower unitcontrasting the force distribution of the frame of the present inventionversus that of the prior art.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to FIG. 1, a gang mower for garden tractors 10 accordingto the present invention includes a frame 11, a hitch 13 and sevenindividual reel-type mower units 12. Frame 11 includes a central portionmade up of a forward sub-frame 20 and a rearward sub-frame 21 arrangedbehind and substantially parallel to the forward sub-frame. Sub-frames20 and 21 are interconnected by a horizontal stiffener 22 and a pair ofarched stiffeners 23 and 24. Forward sub-frame 20, rearward sub-frame 21and horizontal stiffener 22 are preferably made from square metal tubingwelded to one another in a conventional manner. Arched stiffeners 23 and24 are preferably formed from square steel bar stock and welded at eachend to the forward and rearward sub-frames. The shape of the archedstiffeners is best illustrated in FIG. 2.

A pair of brackets 25 are welded to extend forward of forward sub-frame20, and serve as a means by which the central mower in the front row isattached to the frame. Likewise, four substantially identical brackets25 are welded to extend forward of the rearward sub-frame 21, and serveas a means by which the central two mower units 12 in the second row areattached to the frame. Brackets 25 are preferably cut from steel barstock, on the order of at least one quarter inch thick, and welded intoplace. Each of brackets 25 includes a bore that facilitates attachmentof the individual mower units 12 through a pin arrangement (bestillustrated in FIG. 4) that permits the individual mower units to pivotwith respect to the frame about a pivot axes 38. This aspect of theinvention allows the individual mower units to independently pivot andfollow contours 6 encountered as the gang mower is pulled forward overthe ground 5, as shown in FIG. 2.

Hitch 13 is attached to frame 11 via a pair of brackets 26 that aresubstantially similar to brackets 25 discussed earlier. Brackets 26,which are partially obscured in FIG. 1 by upper brackets 126, are weldedto and extend forward from forward sub-frame 20. When the gang mower isreduced to three central mower units and the mower is to be pulled by adraft animal, upper brackets 126 (see also FIG. 2) are used as themounting location for hitch 13 via bore 127. Upper brackets 126 arewelded to arched stiffeners 23 and 24. Hitch 13 includes a pair ofsymmetrically bent square steel bars 72 and 73. Bars 72 and 73 are bentgenerally into the shape shown in FIG. 1 and are welded at a number oflocations along their contact surfaces. A pair of flanges 70 areattached to one end of bar 72 and 73. Flanges 70 are preferably madefrom steel bar stock on the order of about one quarter inch in thicknessand are machined to include a bore 71, which facilitates hitching thegang mower to an ordinary garden tractor in a conventional manner. Theother end of bars 72 and 73 include a bore (not shown) which facilitatesthe attachment of hitch 13 to brackets 26 via a pair of nut/bolts 75.Thus, hitch 13 has the ability to pivot with respect to frame 11 aboutaxis 74 to better facilitate the gang mower following contours whengoing over the top of hills or the bottom of valleys between hills.Furthermore, this feature allows the hitch to be pivoted to an uprightstowed position (FIG. 3) to better facilitate storing the gang mower ina relatively small space.

Attached to the rigid central frame 11 are four outer sub-frames 30. Inparticular, FIG. 1 shows a forward left sub-frame, a forward rightsub-frame, a rearward left sub-frame and a rearward left sub-frame.Although the outer sub-frames 30 are located in different positions andinverted with respect to one another, their individual structures aresubstantially identical. In particular, each outer sub-frame 30 includesa length of square tubular stock welded adjacent one end to a pair ofextension members 31, which are preferably cut from a length of steelbar stock on the order of about one quarter inch in thickness.Extensions 31 each include a bore that permits attachment to the centralframe 11 via a nut/bolt set 36, as best shown in FIG. 4. This permitsthe outer sub-frames to pivot about individual horizontal axes 37a-d.This allows the outer mower units to float with the contour of the lawnindependently of one another. Also, outer sub-frames 30 have the abilityto pivot to an upright stowed position (FIGS. 3 and 4) in order tobetter facilitate storage of the gang mower in a relatively small space.Outer sub-frames 30 also include a pair of brackets 33 and 34 which aresubstantially similar to brackets 25 discussed earlier, except thatbracket 34 is slightly longer and welded to one end of the particularouter sub-frame 30. Brackets 33 and 34 include a bore that facilitatesan attachment of a mower unit 12 via a pin arrangement that permitspivoting about a horizontal axis 38. Thus, the outer sub-frames canpivot about first horizontal axes 37a-d and each of the mower units canpivot about a separate and perpendicular horizontal axis 38. Thispermits the outer mower units to have two degrees of rotational freedomso that gang mower can easily follow virtually any ground contour.

The individual reel-type mower units 12 are commercially available froma variety of known sources, and can be utilized without modification inthe present invention. Each mower unit includes a pair of forward wheels80 and 81 that define a localized forward axis 88. Each mower alsoincludes a rear roller 82 with the ability to rotate about a localizedrearward axis 89. Real roller 82 and forward wheels 80, 81 areinterconnected via a pair of supports 87. Rotating blades 83 areattached between supports 87 and are driven to rotate adjacent cuttingbar 85 when four forward wheels 80 and 81 are rotated in the forwarddirection. A stabilizer bar 84 extends between brackets 87, andapparently serves to give the individual mower unit 12 greater rigidity.The mower units also include a pair of handle mounting studs 86 whichwill be discussed infra in relation to FIG. 5. Thus, mower units 12 areoff the shelf components except that the individual handles for thereel-type mowers are excluded. Cutting height can be adjusted byconnecting the rear roller 82 to different locations along heightadjustment bracket 40 (see FIG. 2 and 5). Height adjustment brackets arepositioned and attached within a channel on supports 87.

The gang mower of the present invention permits a portion of theindividual mower units 12 to pivot about a pair of mutuallyperpendicular horizontal axes with respect to one another. Furthermore,the pivoting ability of the hitch better facilitates cutting over thetop and at the bottom of relatively steep hills. However, it should benoted that none of the mower units have the ability to rotate withrespect to one another about any vertical axis. This permits the user toback up the gang mower 10 without risking the jack-knifing problemsencountered with prior art mower units that have the ability to rotatewith respect to one another about a vertical axis. This feature alsopermits the mower to effectively complete zero radius turns whilemaintaining the proper overlapping cutting arrangement afforded by thetwo staggered rows of gang mowers shown in FIG. 1.

Although the gang mower 10 shown in FIG. 1 includes seven individualmower units 12, the present invention can also utilize either five orthree mowers if a thinner mower swath is desirable. In its basic form,only the central frame 11 is included with three individual mower units,giving the overall gang mower a cutting swath on the order of about fourfeet. The next extension up to approximately a six foot cutting swath isaccomplished by adding a pair of outer sub-frames 30 to forwardsub-frame 20 as discussed earlier. Such a configuration would have threemowers in the front row and two mowers in the back row and have acutting swath on the order of about six feet or more. The nextenhancement comes by adding another pair of mower units 12 to therearward sub-frame 21 via another pair of outer sub-frames 30. Thus, itshould be clear that the present invention has the versatility toaccommodate several different cutting swaths to suit virtually anyindividual user. Furthermore, maintenance on the present invention isrelatively low since the individual mower units can be replaced at arelatively low cost and the underlying frame is virtually maintenancefree. Prior art mower units are typically specially modified for use inthe gang mower and often require costly maintenance and repairs whenproblems occur.

FIG. 3 shows the gang mower 10 of FIG. 1 in its stowed configuration forstorage. Each of the outer sub-frames 30 has the capability of pivotingabout its individual axis 37a-d (FIG. 1) to an upright stowed position.The outer sub-frames 30 can be locked in their stowed configuration viathe pin arrangement illustrated in FIG. 4. In particular, at theconnection with each outer sub-frame 30 an upright bracket 27 is weldedto the underlying sub-frame 20 or 21 (see FIGS. 1, 2 and 4). Uprightbrackets 27 each include a bore which aligns with bores made throughextensions 31. When in the stowed configuration, these bores align andpermit the insertion of a pin 28 which is kept in place via a retainingpin 29, or another equivalent arrangement known in the art. Thus, eachof the outer units is locked in an upright stowed position and the hitchis pivoted to an upright stowed position when it is desired to store thegang mower. If proper clearances are maintained, the gang mower canstill be pulled forward or pushed in reverse when in its stowedconfiguration as shown in FIG. 3. In such a case, the weight of the gangmower, which is typically on the order of about 200 pounds, is supportedby the three central mower units. Thus, the user can quickly pivot andlock the outer mower units to their stowed configuration and simply backthe gang mower into a storage place within a garage or barn. Gang mower10 takes up the space about equal to that of a motorcycle when in itsstowed configuration, or less than half the space of its deployedconfiguration as shown in FIG. 1.

FIG. 4 is an enlarged view illustrating the interconnection betweenrearward right sub-frame 30 and rearward sub-frame 21. Nevertheless, theattachment of each outer sub-frame to the central frame is identicalsince all the outer sub-frames are structurally identical. As discussedearlier, the framing is attached to the individual mower units via a pinarrangement 35 that permits the mower units to pivot about an axis 38.Outer sub-frame 30 is attached to rearward sub-frame 21 via aligningbores (not shown) which receive a bolt 36a. The bolt is secured inplaced with a conventional nut 36b. When the outer sub-frame 30 ispivoted to its upright stowed configuration, the bores in extensions 31and upright bracket 27 align and permit the insertion of a pin 28. Pin28 is held in place via a removable retaining pin 29 that is insertedthrough a hole in one end of pin 28. When the outer sub-frames 30 arelowered into their deployed configuration, pin 28 is reinserted throughbracket 27 and left in place until needed. The pin and retaining pinarrangement shown for attaching the frames to the individual mower unitsand for locking the outer sub-frames in an upright position could have avariety of other mechanical connections substituted therefore which areknown in the art. For instance, a nut and bolt arrangement could besubstituted for each of the pin/retaining pin connections illustrated.

Referring now to FIG. 5, the force distribution aspect of the presentinvention is contrasted with that of the closest known prior art (Tobin,Jr. U.S. Pat. No. 4,287,706). In particular, FIG. 5 shows a diagrammaticview of a mower unit 12 having a forward wheel 80 that is rotatableabout a forward axis 88. The rear roller 82, which is rotatable about arearward axis 89 is attached to the forward mower via a height adjustingbracket 40. The present invention is preferably attached directly aboverearward axis 89 so that the weight of the frame (Wf) is supported bythe rear rollers. Although the present invention would perform well withthe mowers attached either for or aft of rearward axis 89, attachingdirectly above rearward roller 82 is the most easily facilitated becauseheight adjusting bracket 40 typically includes several bores foradjusting the height of rollers 82. Roller units 12 are preferablyattached directly above roller 82. It is also important to note that theframe is attached lower than forward axis 88 but higher than rearwardaxis 89. The result being that the force (Fp) supplied by pulling thegang mower always intersects a line 90 connecting axis 88 and axis 89.The result being that each individual mower unit is leveraged downwardwhen pulled forward to increase the friction contact between drivewheels 80, 81 and the ground. This contrasts with the Tobin connectionvia a bracket 111 that attaches to handle studs 86. Handle studs 86 aretypically located relatively close to forward axis 88. Thus in the Tobinmower, the majority of the frame's weight is supported by the forwardwheels rather than the rear roller. The consequence being that the rearroller tends to bounce along the ground when the Tobin mower is pulledforward. Tobin attempted to eliminate this problem by including a springwhich constantly supplies a restoring moment to maintain the rollers incontact with the ground. The present invention solves the rollerbouncing problem inherent in the Tobin gang mower.

It should be understood that the above description is intended to serveonly in aiding those skilled in this art to understand the presentinvention, and is therefore intended for illustrative purposes only.Although a number of enhancements to the present invention have beendiscussed above, those skilled in the art may also recognize additionalenhancements to the present invention. For instance, a spiked rollercould be substituted for the smooth rollers 82 illustrated for purposesof allowing the user to aerate their lawns as they mow. Anothervariation might be the inclusion of a slightly modified hitch so thatthe present invention could be pulled by a horse or other draft animal.Still another variation might be accomplished by utilizing reel-typemowers that have no rear roller. In such a case, the frame might besupported by its own rollers or wheels attached at strategic locationswith the ability to adjust the height of the frame off the ground inorder to adjust the cutting height of the individual mower units. Thus,while it may be preferable to use off the shelf reel-type mowers,modifications can be made to the illustrated invention without departingfrom the intended scope of the present invention.

Still other enhancements to the present invention might includeutilizing the present frame with a plurality of golf ball retrieverssubstituted in place of the reel-type mower units. Such an alternativemight prove attractive in retrieving balls at driving ranges. Thepresent invention could also be utilized as a trailer for a number ofother lawn implements including aerators, fertilizer units, or any othersuitable lawn implement that could be substituted for the reel-typemower units illustrated. There is also the possibility of attachingimplements requiring electrical power to the frame of the presentinvention and supplying power via a hook up to the alternator or batteryof the garden tractor. This possibility may be especially attractive inattaching a number of weed eater units to the frame in order to cut anystemmy weeds or fesque grasses that are difficult to cut in a singlepass with a reel-type mower. Finally, there is also the possibility ofmounting a fertilizer tank on the frame and running a number of nozzlesfrom the tank along the rearward base of the frame so that the usercould distribute liquid fertilizers over their lawn while cutting. Thus,the above description is clearly not meant to limit in any way theintended scope of the present invention, which is defined solely interms of the claims as set forth below.

I claim:
 1. A gang mower comprising:a frame having a weight; a pluralityof reel-type mowers each having forward wheels and a rear roller, saidforward wheels being rotatable about a forward axis, and said rearroller being rotatable about a rear axis that is substantially parallelto said forward axis; a hitch attached to and extending forward fromsaid frame; said frame being attached to each of said reel-type mowershigher than said rear roller, lower than said forward axis and asufficient distance away from said forward axis toward said rear axisthat a majority of said weight is supported by the rollers of saidreel-type mowers instead of the forward wheels of said reel-type mowers;and wherein said frame pushes said reel-type mowers forward when saidframe is pulled forward by said hitch.
 2. The gang mower of claim 1,wherein said frame is attached to each of said reel-type mowerssubstantially directly above said rear axis.
 3. The gang mower of claim1, wherein said frame is substantially rigid with respect to a verticalaxis such that the relative positioning of said reel type mowers in aplane perpendicular to said vertical axis remains substantially constantregardless whether the gang mower is being pulled forward around curvesor pushed backward.
 4. The gang mower of claim 1, wherein each of saidreel-type mowers are attached to said frame at pivot points, and each ofsaid reel-type mowers can pivot with respect to said frame about ahorizontal axis through said pivot points.
 5. The gang mower of claim 4,wherein said hitch is substantially rigid with a forward end connectableto a garden tractor and a rear end attached to said frame at at leastone hitch pivot point, and said hitch can pivot with respect to saidframe about a horizontal axis through said at least one hitch pivotpoint.
 6. The gang mower of claim 1, wherein said frame includes acentral portion and a plurality of outer portions;each of said outerportions being attached to said central portion at at least onecontouring pivot point, and said outer portions can pivot with respectto said central portion about a horizontal axis through said at leastone contouring pivot point; and said horizontal axis is perpendicular tosaid forward axis.
 7. The gang mower of claim 6, wherein one of saidreel-type mowers is attached to each of said outer portions;each of saidouter portions can pivot between a deployed position and an uprightstowed position; and the gang mower further comprises means for lockingeach of said outer portions in said stowed position.
 8. The gang mowerof claim 7, wherein the gang mower covers a large area when said outerportions are in said deployed position, but covers a substantiallysmaller area when said outer portions are in said stowed position.